I'm soon going to integrate my three 7 week old chicks with five 19 week old pullets. What feed do you recommend I put them all on? I've been looking at All Flock, but I can't decide on a brand. As a sidenote, is it okay to switch the pullets off of their layer feed right now? I just put them on it a little under two weeks ago. Should I wait a while until I switch their feed again?